Recently, there are proposed such techniques as forming an inorganic film on various kinds of base materials for the purpose of providing various functions to the base material. As one of these techniques, Patent Document 1 discloses a flaky titanic acid suspension that is obtained by treating a layered titanate with an acid and then having a basic compound act thereon for causing interlayer swelling or separation, and a titanic acid coating film obtained by coating and drying the flaky titanic acid suspension on a base material such as a resin film. The titanic acid coating film is formed by a very simple method for forming a coating film, and, as described in the Patent Document, it is expected to exert such effects as antireflection, high dielectric constant, photocatalytic action, ultraviolet ray shielding and heat ray reflection.
As described later, Patent Documents 2-4 disclose a method for producing a layered titanate. And, as described later, Patent Documents 5 and 6 disclose a method for producing a flaky titanic acid suspension.    Patent Document 1: WO 03/016218    Patent Document 2: Japanese Patent No. 2979132    Patent Document 3: WO 99/11574    Patent Document 4: Japanese Patent No. 3062497    Patent Document 5: Japanese Patent No. 2671949    Patent Document 6: WO 03/037797